596 [December 



rior extremity red, .20 inch long and .08 inch in diameter, of a cylindrical form, 

 slightly tapering and obtusely rounded at both ends, but more so at the poste- 

 rior than at the anterior extremity. A slightly projecting jjoint perceptible at 

 the apex of the anterior end, and two similar projections at the opposite extre- 

 mity. The larva is composed of nine segments, each well marked by a contrac- 

 tion intervening at the joints. The anterior or head segment is the largest, and 

 has near the tip on the under side two small black lines, slightly diverging 

 from each other as they proceed forwards. A dorsal row of deep pink spots of 

 a square or trapezoid form on each segment, reaching from its anterior edge 

 about J of the distance across the segment: a very slender pink-red line reach- 

 ing backwards from each stigma across the segment; and a similar line from 

 each of the dorsal spots. Other lines of the same color are often visible upon 

 the surface, branching from and anastomosing witli these like blood-ve.ssels. 



"Pupa. Plate II. fig. 2. — The dimensions do not differ perceptibly from those 

 of the larva. The abdominal segments are of the same orange color as the 

 larva ; but the future head, thorax and wings are sanguineous-red and lustrous. 



•'Imago. Cec Salicis Fitch, {=rigidcE 0. S.) Plate II. fig. 1. — Black, hirsute: 

 wings lurid; venter with white pubescence: legs lurid. Length .18 inch. Ex- 

 panse wings ..35 inch. 



"Head with a ruffle of fine, velvet-like hairs surrounding its base. Antennae 

 shorter than the thorax, moniliform, slightly and gradually diminished in dia- 

 meter towards their tips ; joints 20 in number "J, [ 9 ]' each with a few very mi- 

 nute hairs directed forwards, 16 [26?] in number 9 [SI' each verticillated with 

 longer and coarser hairs. Thorax with two impressed, longitudinal lines on 

 the back, slightly converging posteriorly, and densely set with minute hairs; 

 the intermediate space glabrous : sides with longer hairs, most conspicuous 

 and thickly set forward of the wings. Abdomen with the posterior edge of each 

 segment marked above by a lighter tinge, beneath chestnut brown, thickly 

 covered with short, white hairs of a silky lustre. Abdomen 9 [%] terminated 

 by a slightly exserted, two-jointed ovipositor [% forceps] of a cinnamon yellow 

 color. Legs glabrous, long and slender, the hinder ones extending .27 inch, of 

 which the tarsi measure .13 inch, blackish above, beneath lurid brown; tarsi 

 black, the first joint very short, the third [second] longest and most slender, the 

 fourth and fifth broadest. Wings smoky brown, translucent, the nervures ex- 

 cept the anal [3rd longitudinal] rectilinear; the postcostal [2nd longitudinal] 

 longest, running direct to the tip of the wings; the medial [anterior branch of 

 3rd longitudinal] scarcely confluent with the inner margin at | the distance 

 from the base to the tip, towards its base becoming a mere plait-like trace upon 

 the wing, and at the first glance seeming to be a branch of the anal nervure 

 [3rd longitudinal.]" 



On comparing tlie average dimensions of J.'r. Fitch's gall with those 

 of the gall found by myself on S. humilis, the former averages 1.12 inch 

 long and the latter only .77 inch long, and the diameter of the former 

 is given as .37 inch while the average diameter of the latter is only .27 



